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In the December 2017 System Guide, we discovered the unexpected. Given the bevy of pre-built computing devices now available, there's a lot of debate and confusion about building one yourself these days. What's the goal behind a custom PC build in 2018? What makes a certain hardware choice "right" to support that?

Further Reading

So rather than starting 2018 with a traditional guide—where Ars presents three build ideas and a set of specific hardware to accomplish each—we're going to take a step back. This will be more of a meta-guide than an actual guide; we're going to share the methods and mechanics behind putting together your favorite long-running PC building guide. So while this guide will build from a set of three major system design goals like always, this edition will go through each major PC hardware component one by one, focusing more on ideology than instruction, discussing how a specific part does (or doesn't) contribute to a specific construction goal.

Standard system design goals

It's not enough to say a system should be "fast" just like it's not enough to sum up a sports car with its 0-60 time on a track. A gaming-focused system that impressively renders the most demanding scenes in Crysis can still be frustratingly slow to boot... and may handle the same gaming scenes abysmally if you forgot to (or didn't want to) close your email client or your 30-tab Web browser first. A system with server intentions may effortlessly run five or 10 entire virtual machines but similarly stumble on a single demanding application. Meanwhile, a five-year-old system that doesn't have very impressive specs might feel surprisingly fast. You know you're not going to play the latest AAA games in 4K on it, and you don't expect it to handle 200 tabs in Chrome, but somehow, despite how old it is, such a build can feel comfortable.

Generally speaking, the three machines described above are archetypical of three high-level system characteristics we'll be outlining: general performance, multitasking, and frames per second (or FPS for short).

General performance

This category may be the most ambiguous, therefore it's the most contentious when determining which parts make sense. When we talk about "general performance" in the scope of the system guide, we're not talking about crushing any individual benchmark with super high numbers. What we're actually talking about is bottleneck elimination. A system with high general performance doesn't feel sluggish—even if it doesn't have the biggest, beefiest parts—because its performance is as consistent as possible. When you double-click an icon on the desktop, you have an expectation of how long it will take to open the application or document. Any machine with high general performance reliably satisfies that expectation. A machine more heavily focused on application-specific performance might frequently flail.

General performance machines likely work for the largest amount of common use cases. It's entirely possible to build a machine that gets really great framerates in all your games, but such a machine can be massively frustrating because it takes three or four times longer to start an app (including a game) than others. At the same time, an older general performance machine that benchmarks out slower may feel better if it pushes two-thirds of the general framerate but doesn't have those irritating, immersion-breaking "lurches" once or twice in a 15 minute session of play. (This isn't just a gaming thing, either. The same is true of machines that usually open Office documents in 300ms but occasionally take 1500ms for no immediately obvious reason or machines that take 500ms to open the same document but take that 500ms every time.)

An ideal general performance machine has as much to do with human psychology as it does with actual hardware. I've always been fond of a psychology study I read in the '90s (which I've sadly been unable to find again) that outlines something called a 33-percent "expectation threshold." As I recall it, most people won't notice a change in how long it takes a task to complete if it changes by less than a third in either direction. It doesn't really matter how long you expect a task to take in the first place—a one-second task seems "a little quicker than usual" at 667ms and "slower than usual" at 1333ms. A one-hour task doesn't start seeming "slow" until 80 minutes, and (without measuring it deliberately) it won't really seem "fast" if it's not done in 40 minutes.

This 33-percent approach has become a great rule of thumb for me when approaching performance over the years. My other favorite rule of thumb is that people remember unpleasant surprises far longer and more vividly than they remember pleasant ones. If you give someone an unexpected win in one hand and an unexpected loss in the other, they will more than likely complain about how much better things used to be. So if you build someone an expensive gaming machine that feels slow and clunky sometimes, they generally won't speak kindly of the experience, either.

Multitasking

Multitasking, like general performance, is more important than it might first appear. It's obvious that a system expected to run a few virtual machines will need to multitask well; ditto for a graphics workstation where you might want Blender and Photoshop open and running simultaneously. However, the ability to handle lots of tasks at once is relevant for any modern general-purpose computer. The operating system itself places frequent multi-tasking demands on a system—and modern users do, too—more than we realize.

If you want to be able to keep your email client up and running all the time so you'll get notifications when that thing from your boss/ message about your date tonight arrives as you play your game... well, that's multitasking. That email client isn't "free" in terms of system resources. Want to keep a game Wikia up in your browser for reference while you play? Again, multitasking.

There is a lot of overlap between multitasking and general performance; you're unlikely to have a machine that exhibits good, consistent performance without several good multitasking characteristics. But it's worth considering these characteristics separately—just as it's worth breaking FPS out next—because you can and may want to take multitasking out to extremes that no longer really affect general performance. Such situations might include VM servers or battle stations that you want to both host and play games on, for instance.

FPS

Thus far we've defined what a category is, but let's discuss what FPS isnot. When you're chasing FPS, you're looking for a high overall number of rendered frames per second in games. This does not cover how long it takes to load the game, how long it takes to "zone" in massive landscape games found in WoW, or even how frequently you have irritating 50-500ms "lurches" where your framerate stumbles for just long enough to break immersion. FPS is only about how many frames per second you can expect to render in a given scene of a given game when everything is working right.

Further Reading

(Editor's note: If you think it sounds like I don't think as highly of FPS as I do of the other characteristics, I won't argue with you.)

FPS is important. Most gamers will want base framerates above 60 FPS in even the most demanding scenes of a game. With that said, I will caution anyone who'll listen that there is a big difference between being unhappy with the way a game looks and plays and being unhappy about the number in the FPS counter you've chosen to keep in one corner of the screen. If you want game immersion, you're usually better off killing the FPS counter and addressing the things that make the game occasionally immersion-breakingly slow. Obsessing about whether an icon says "130FPS," "110FPS," or "90FPS" while a game is running fine does nothing.

Here's the deal: you hopefully already know that RAM, your system's memory, is a couple orders of magnitude faster than even the speediest solid state drive. And you probably already know that if you don't have enough RAM to hold your programs, they can't actually run. The missing factor here is cache.

Remember that RAM is a couple orders of magnitude (100x or more) faster than even the speediest solid state disk,

I think of the two, ram prices are the ones to ignore. As long as you can afford it, don't wait on ram prices. GPU prices however are already showing signs of coming down.

Buy at Fry's, microcenter, Newegg if you can. Research at Newegg, Tom's, anandtech. Use Amazon if you must, but remember to check the actual seller out first.

I just upgraded to a ryzen chip and board and it's never been easier. Got first bit just fine. Just remember to check chip/Mobo compatibility, case sizes, Mobo ports and the PSU strength. And Mobo firmware if you're going on a brand new chip. Then validate your Windows license.

I'd consider including a note about networking -- specifically wired vs. wireless. It's (still) my opinion that wired networking is highly preferable for assured, consistent performance. Even most of the telco routers I've seen have a four-port switch integrated as well as wifi.

Nice to see a emphasis on performance consistency in one of these guides. A little more discussion around cooling would be a good addition, especially as not all CPU's come with coolers.

Ars wrote:

You should absolutely take advantage of the fastest RAM your CPU architecture supports, and, if you can, make sure you have enough separate physical DIMMs (dual in-line memory module) to feed all the available channels.

One thing to watch out for are memory sticks with obnoxiously large heatsinks. These can interfere with larger CPU coolers if you're not careful.

Ars wrote:

A gaming system with a high-end GPU is the biggest hog, and that should probably be spec'd out with a PSU rated at least 750W (a GTX 1080Ti, for example, can draw 300W all by its lonesome).

That may be true while running stress tests, but it's rare for a game to maximize utilization of both the GPU and CPU simultaneously. A 750W PSU with lots of 12V capacity would be more than enough in a non-overclocked gaming rig.

For a storage system with multiple hard drives (10 or less), 500W or thereabouts will generally do the trick. A gaming system with a high-end GPU is the biggest hog, and that should probably be spec'd out with a PSU rated at least 750W (a GTX 1080Ti, for example, can draw 300W all by its lonesome).

The spec sheet says the 1080TI will draw 250w and Nvidia recommends a 600W system. And considering these system estimates have to account for really crappy PSUs, that 600W will likely be overkill.

Nice to see a emphasis on performance consistency in one of these guides. A little more discussion around cooling would be a good addition, especially as not all CPU's come with coolers.

Ars wrote:

You should absolutely take advantage of the fastest RAM your CPU architecture supports, and, if you can, make sure you have enough separate physical DIMMs (dual in-line memory module) to feed all the available channels.

One thing to watch out for are memory sticks with obnoxiously large heatsinks. These can interfere with larger CPU coolers if you're not careful.

Ars wrote:

A gaming system with a high-end GPU is the biggest hog, and that should probably be spec'd out with a PSU rated at least 750W (a GTX 1080Ti, for example, can draw 300W all by its lonesome).

That may be true while running stress tests, but it's rare for a game to maximize utilization of both the GPU and CPU simultaneously. A 750W PSU with lots of 12V capacity would be more than enough in a non-overclocked gaming rig.

[edit] CPU coolers, not heatsinks

Another consideration is using more than 2 sticks in a dual channel board. It has a slight performance hit.

Nice to see a emphasis on performance consistency in one of these guides. A little more discussion around cooling would be a good addition, especially as not all CPU's come with coolers.

Ars wrote:

You should absolutely take advantage of the fastest RAM your CPU architecture supports, and, if you can, make sure you have enough separate physical DIMMs (dual in-line memory module) to feed all the available channels.

One thing to watch out for are memory sticks with obnoxiously large heatsinks. These can interfere with larger CPU coolers if you're not careful.

Ars wrote:

A gaming system with a high-end GPU is the biggest hog, and that should probably be spec'd out with a PSU rated at least 750W (a GTX 1080Ti, for example, can draw 300W all by its lonesome).

That may be true while running stress tests, but it's rare for a game to maximize utilization of both the GPU and CPU simultaneously. A 750W PSU with lots of 12V capacity would be more than enough in a non-overclocked gaming rig.

[edit] CPU coolers, not heatsinks

Another consideration is using more than 2 sticks in a dual channel board. It has a slight performance hit.

If you want to use 4 sticks find a quad channel board.

The memory controller is a feature of the CPU, not the motherboard, and comes with quite the price premium. Ie., on the AMD side of things, you'd need a Threadripper (or Epyc) CPU, with a fitting MB.

But yeah, if you're building a system with dual channel capable CPU, leaving 2 memory slots open gives you the ability to expand further in the future. It will often allow you to ignoring future proofing your system, and instead just get the amount of memory you need now.

If you're going with a 2-slot board, you'd have to think down the road, or face potentially having to throw away memory, if your requirements change.

Nice to see a emphasis on performance consistency in one of these guides. A little more discussion around cooling would be a good addition, especially as not all CPU's come with coolers.

Ars wrote:

You should absolutely take advantage of the fastest RAM your CPU architecture supports, and, if you can, make sure you have enough separate physical DIMMs (dual in-line memory module) to feed all the available channels.

One thing to watch out for are memory sticks with obnoxiously large heatsinks. These can interfere with larger CPU coolers if you're not careful.

Ars wrote:

A gaming system with a high-end GPU is the biggest hog, and that should probably be spec'd out with a PSU rated at least 750W (a GTX 1080Ti, for example, can draw 300W all by its lonesome).

That may be true while running stress tests, but it's rare for a game to maximize utilization of both the GPU and CPU simultaneously. A 750W PSU with lots of 12V capacity would be more than enough in a non-overclocked gaming rig.

[edit] CPU coolers, not heatsinks

Another consideration is using more than 2 sticks in a dual channel board. It has a slight performance hit.

If you want to use 4 sticks find a quad channel board.

The memory controller is a feature of the CPU, not the motherboard, and comes with quite the price premium. Ie., on the AMD side of things, you'd need a Threadripper (or Epyc) CPU, with a fitting MB.

But yeah, if you're building a system with dual channel capable CPU, leaving 2 memory slots open gives you the ability to expand further in the future. It will often allow you to ignoring future proofing your system, and instead just get the amount of memory you need now.

If you're going with a 2-slot board, you'd have to think down the road, or face potentially having to throw away memory, if your requirements change.

I think you overlooked RAM speed in connection to both general performance and FPS. For CPU-bound games especially, the difference between running at a lower speed and even just turning on XMP (or installing faster RAM) can be significant.

And even for general performance, depending on the workload of course, high CPU can actually be stalled waiting on RAM. (And other I/O of course).

I feel like this article shouldn't have been named "Ars Technica System Guide, Spring 2018". Personally I use Ars System Guide to keep updated on what are the good components at a given time without having to do a ton of research myself.I can see the value of this article for people new to PC building, but it's really not what I expected from the title.

I wouldn't have thought about that as part of "build", but you're absolutely 100% right about that. Wired networking (assuming we're talking actual ethernet, not powerline) always kicks the living crap out of wifi, period. Especially in terms of consistent, low latency.

Yep, that's where everything really ends up, where the rubber hits the road, your monitor. In my view, you should pick your monitor (or your eventual intended monitor) first. Once you know the resolution you're trying to game at, that will lead in a nice chain to the other components you want. First buy a graphic card that drives that resolution well (and remember that no graphic card on the market can drive 4K at the highest settings), then buy a CPU that drives that card well at that resolution. Buy enough RAM to run your intended games (16 gigs is typically fine), and buy an SSD of some kind. Any SSD is really fine. The speedup from rust to SSD is gigantic. The additional speedup from a slow SSD to a fast one is incremental, probably well below the 33% margin. And then buy a power supply, case, keyboard, and mouse.

That's the way I approach current-gen gaming, at least. Resolution first, then everything falls into place from there.

Here's the deal: you hopefully already know that RAM, your system's memory, is a couple orders of magnitude faster than even the speediest solid state drive. And you probably already know that if you don't have enough RAM to hold your programs, they can't actually run. The missing factor here is cache.

Remember that RAM is a couple orders of magnitude (100x or more) faster than even the speediest solid state disk,

We all do it...

D'OH!

I caught some minor errors this morning that I can blame on editors... but that one's all mine.

First buy a graphic card that drives that resolution well (and remember that no graphic card on the market can drive 4K at the highest settings), then buy a CPU that drives that card well at that resolution.

You're right, 4K AAA gaming is really an exercise in frustration... which is why it didn't occur to me to lay it out like that this time, because for the past several years, who's targeting below 1080P?

I was trying to write this as a fairly "evergreen" piece though, so thanks for laying this out. 4K gaming should get a lot more reasonable in a few years.

Jim, the technical information is much appreciated. Just the part describing the real world performance of storage alone makes this a very valuable article.

Thank you! I wasn't sure how it would be received, to be honest, but the feedback from the last one made me think we all needed to get on the same page with how we think and talk about the components before we can get back to the usual rounds of picking our favorites and calling each other names about how bad each others' choices are.

Appreciate the author taking the time to teach a man to fish rather than handing him one. I've been guilty of being that lazy saying "Well, it's good enough for Ars. Specs line up - let's throw it in." in the past.

Better to do your own research than to rely on someone telling you what to use and yelling at them later when your build fails.

Another consideration is using more than 2 sticks in a dual channel board. It has a slight performance hit.

It'll be a challenge finding an application that sees a bigger performance hit from multiple sticks in a dual channel board than the performance boost the system gets from having a lot more RAM, though.

With that said, the same amount of RAM in two DIMMs rather than four usually is a good idea... not for any tiny performance difference, but because that means you're less likely to need to throw away smaller DIMMs to make room for bigger ones on your next system upgrade.

It seems like it would be eminently feasible to have a guide that both provides specific examples of contemporaneous components at multiple price points and outlines the general contribution of each major component type to general and gaming performance, with actual data.

Further, it could provide a nice opportunity to actually test the contribution of actual components. You might end up with Power Supply advice that mirrors that of the actual hardware manufacturers, for one!

Well put together article, but insufficient on specific use cases. 'Multitasking' is a fine thing, but how much does a typical multitasking user need?

Power users will take all they can get, but many others would be considered multitaskers yet rarely peg a four core processor, let alone a sixteen thread one. If one is the latter category (as opposed to the former, where you would likely know already) one could end up buying a lot more CPU than needed.

This is the first system guide since the Vega graphics Ryzen chips came out, which would be very, very interesting to compare across a range of real workloads. Who's going to experientially benefit from a more potent CPU with much inferior graphics (more expensive Intel CPUs) for example?

Only thing I would add is in the Motherboard section.These days, I would limit my Motherboard searches to those containing two, or preferably three, M.2 sockets. Those SSDs can be up to ten times faster than conventional SSDs, and possibly cheaper to boot. Some M.2 sockets suck up two SATA channels, so watch for that in planning your SATA devices.

This is the first system guide since the Vega graphics Ryzen chips came out, which would be very, very interesting to compare across a range of real workloads. Who's going to experientially benefit from a more potent CPU with much inferior graphics (more expensive Intel CPUs) for example?

Now I'll argue that Intel no longer has the performance crown clock for clock once both rigs have tightly timed memory. Ryzen benefits more from it but Intel chips also enjoy increased system stability when they aren't brute forcing for big numbers. Especially if they haven't been de-lidded.

This is the first system guide since the Vega graphics Ryzen chips came out, which would be very, very interesting to compare across a range of real workloads. Who's going to experientially benefit from a more potent CPU with much inferior graphics (more expensive Intel CPUs) for example?

One non-performance thing I liked about Ryzen was that I found it simpler to install than Intel. And mine came with a much better stock cooler. Although maybe this is subjective.

Have the current gen CPUs all received baked-in Spectre, etc. patches?

With word that the patches reduced performance, is there an CPU architecture to hold out for that won't take the same hit?

You'll probably be wanting to wait at least a few processor generations if you want an actual fix rather than workarounds. Even then I'd doubt we'd have a truly performant fix without changing the way software interacts with the CPU. The x86/x64 interface emulates a hardware model that is very removed from how modern processors actually work.

I've always taken the approach of building for my use case, rather than optimizing in the abstract. My primary uses are high resolution gaming and office productivity. I prioritize selection of my components based on those uses. High resolution gaming is by far the most resource intensive, so I start there. I know I'll need a beefy graphics card, so I build around it. Motherboard, case layout, and PSU will all need to accommodate the card. CPU, RAM, and storage all need to be optimized to push pixels to the card as fast as possible without latency or bottlenecks. There's a bit of esoterica to consider with respect to PCI lanes, cache and the like, but for the most part, I know that if everything supports optimal GPU performance, then my general purpose computing and gaming needs will be satisfied. Of course, selecting a monitor to display those pixels on is an art in itself.

It strikes me the weighting you have given to motherboards, cases and power supplies are simply too low.

As has been seen this past year, initial offerings for Ryzen were somewhat meh in terms of RAM compatibility which has subsequently been quite improved through firmware updates. Not all board manufacturers do this. Some never do updates. This similarly applies to component driver software updates, as some are provided by manufacturer and some rely on the chip maker, like RealTek for example. A careful analysis of the different manufacturers is required to procure a decent board as the range of quality is far too high to boil down in a simple weighting system. a decent quality board is not to be dismissed lightly as it will affect all the other components irregardless of the intended use.

Cases need to have adequate space and cooling otherwise one simply wastes otherwise expensive parts due to the heat retention of the inadequate case. My own builds are NEVER in glass sided boxes due to it being an insulator with no real upside other than the pretty lights some seem so enamored with.

A quality power supply that is large enough for the use case is a mandatory requirement. One can easily use a supply that produces more power than is needed but NEVER EVER one that is too small or of questionable heritage. There are tools to measure the relative outputs, such as Thermaltake's Dr. Power II, which will test all the current standard plugs. No need to guess here.

I would suggest each of these components should receive an equal rating on par with the others and as each is as critical irregardless of the use case there should be no short cuts or diminution as to importance. Like a chain, each build is as strong as the weakest link.